MAUDE Adverse Event Report: Nihon Kohden Corporation ZM-531PA; Telemetry Transmitter

Model Number	ZM-531PA
Medical Device Problem Codes	Display or Visual Feedback Problem (1184); Incorrect, Inadequate or Imprecise Result or Readings (1535); Output Problem (3005)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	04/26/2026
Type of Reportable Event	Malfunction
Event or Problem Description
The customer reported that lead 1 waveform is inverted on this transmitter.The unit was not in patient use at the time.
Additional Manufacturer Narrative
The customer reported that lead 1 waveform is inverted on this transmitter.According to the customer, the unit was connected to a simulator and the device produced an inverted waveform.The unit was not in patient use at the time.Nihon kohden continues to investigate the reported event.Nihon kohden will submit a supplemental report in accordance with 21 cfr section 803.56 when additional information becomes available.The following field contains no information (ni), as attempts to obtain the information were made, but not provided: d10 attempt # 1: 05/07/2026 emailed the customer via microsoft outlook for the information in the ni list above: no reply was received.Attempt # 2: 05/12/2026 i called (b)(6) to ask for model and serial numbers of any devices the reported device was connected or related to.A message was left for (b)(6) to call me back with this information.Attempt # 3: 05/15/2026 i called (b)(6) to ask for model and serial numbers of any devices the reported device was connected or related to.A message was left for (b)(6) to call me back with this information.

• Brand Name: ZM-531PA
• Common Device Name: Telemetry Transmitter
• Manufacturer (Section D): Nihon Kohden Corporation; attn: shama mooman; 1-31-4 nishiochia; shinjuku-ku, tokyo 161-8 560; JA 161-8560
• Manufacturer (Section G): Nihon Kohden Tomioka Corporation; attn: shama mooman; 1-1 tajino; tomioka city, gunma 370-2 314; JA 370-2314
• Manufacturer Contact: shama mooman ; seibu bldg 2, 4th floor 1-11-2; kusunokidai tokorozawa, saitama 359-8-580 ; JA 359-8580
• MDR Report Key: 25258936
• Report Number: 8030229-2026-06570
• Device Sequence Number: 10541518
• Product Code: DRT
• UDI-Device Identifier: 04931921115107
• UDI-Public: (01)04931921115107
• Combination Product (Y/N): N
• Initial Reporter State: NY
• Initial Reporter Country: US
• PMA/510(K) Number: K043517
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: User Facility
• Initial Reporter Occupation: Biomedical Engineer
• Type of Report: Initial,Followup
• Report Date (Section B): 07/27/2026

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Operator of Device: Health Professional
• Device Model Number: ZM-531PA
• Device Catalogue Number: ZM-531PA
• Was Device Available for Evaluation?: Yes
• Date Returned to Manufacturer: 05/13/2026
• Is the Reporter a Health Professional?: No
• Was the Report Sent to FDA?: No
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 04/26/2026
• Supplement Date Received by Manufacturer: 07/22/2026
• Initial Report FDA Received Date: 05/22/2026
• Supplement Report FDA Received Date: 07/27/2026
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 05/10/2019
• Is the Device Labeled for Single Use? (Y/N): No
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Reuse
• Patient Sequence Number: 1
• Patient Sex: Unknown